JP5058085B2 - Substrate cleaning device - Google Patents

Description

  The present invention relates to a substrate cleaning apparatus for cleaning and removing particles adhering to a substrate surface such as a semiconductor wafer or an FPD (flat panel display) substrate.

  In general, in the manufacture of a semiconductor device, a photolithography technique is used to form an electrode pattern on, for example, a semiconductor wafer or an FPD substrate (hereinafter referred to as a wafer). In this photolithography technique, a photoresist solution is applied to a wafer or the like by a spin coating method, the resist film formed thereby is exposed according to a predetermined circuit pattern, and this exposure pattern is developed to form a resist film A circuit pattern is formed.

  Further, in the semiconductor device manufacturing process, it is extremely important to keep the wafer and the like in a clean state. For this reason, before and after each processing process, a cleaning device for cleaning and removing particles adhering to the wafer or the like is provided as necessary.

  Conventionally, a spin chuck that holds a wafer horizontally and rotates about a vertical axis, a cup that surrounds the outside of the spin chuck, a cleaning member that can rotate about the vertical axis, a rotation mechanism that rotates the cleaning member, and a cleaning member And a moving mechanism that moves the wafer along the surface to be cleaned of the wafer.

In this type of substrate cleaning apparatus, for example, a sponge made of PVA (polyvinyl alcohol) is used as a cleaning member, and a groove-shaped recess opening from the center to the side is provided on the cleaning surface of the sponge. There is known a structure in which a cleaning liquid discharge port is communicated with the central portion of the head (for example, see Patent Document 1). In this way, a new cleaning liquid is always supplied to the central portion of the cleaning member by communicating the cleaning liquid discharge port with the central portion of each groove-shaped recess.
Japanese Patent No. 3059641 (paragraph 0027, FIGS. 5 and 6)

  However, since the technique described in Patent Document 1 is provided with a groove-like recess opening on the outer periphery of the cleaning surface of the cleaning member, the cleaning liquid discharged from the groove-like recess during the cleaning process is scattered on the outer periphery and hits the cup. There is a problem that a part of the liquid rebounds to generate mist, and the mist is reattached to the wafer surface.

  The present invention has been made in view of the above circumstances, and provides a substrate cleaning apparatus capable of suppressing the occurrence of mist due to a cleaning liquid splashing outward during a cleaning process and preventing reattachment to the substrate. With the goal.

In order to solve the above problems, a substrate cleaning apparatus according to the present invention includes a holding unit that holds a substrate to be processed horizontally and rotates around a vertical axis, a cleaning member that can rotate around a vertical axis, and the cleaning member. In a substrate cleaning apparatus comprising: a rotating mechanism for rotating; and a moving mechanism for moving the cleaning member along a surface to be cleaned of the substrate to be processed. The cleaning member joins a sponge-like cleaning base to a base portion. A cleaning liquid discharge port connected to a cleaning liquid supply source is provided in the central part of the base part and the cleaning base part. The base end of the cleaning base part communicates with the cleaning liquid discharge port, and the distal end is outside the cleaning member. A plurality of communication grooves extending to the front side of the peripheral portion are provided, and a discharge hole communicating with the communication groove is provided at a position where the communication groove is located in the base portion, and at least the communication groove of the communication groove and the discharge hole is cleaned. Part It has an inclined surface toward the washing backside from the cleaning surface along the rotational direction of, characterized in that (claim 1). In this case, it is preferable to further provide a buffer communication hole formed in the central portion of the cleaning base portion having a diameter larger than that of the cleaning liquid discharge port of the base portion and communicating with the cleaning liquid discharge port and each communication groove.

  With this configuration, the cleaning liquid discharged from the cleaning liquid discharge port at the center of the cleaning member that rotates about the vertical axis in a state where the surface to be cleaned of the substrate to be processed and the cleaning surface of the cleaning member are close to each other. The cleaning process can be performed by forming a clean liquid film to be replaced, and the particles removed by the cleaning member and the cleaning liquid used for the cleaning can be discharged from the communication groove and the discharge hole to the cleaning back surface side. Further, since the particles removed by the cleaning member and the cleaning liquid used for cleaning are discharged from the outer peripheral side (periphery side) of the cleaning member to the cleaning back surface side, the number of rotations of the cleaning member can be set high. It becomes possible. In this case, the cleaning base is formed with a larger diameter than the cleaning liquid outlet of the base portion, and the cleaning liquid outlet and the buffer communication hole communicating with each communication groove are provided to discharge (supply) from the cleaning liquid outlet. The cleaning liquid to be discharged can be made to flow evenly and smoothly into each communication groove (claim 2).

Further, according to the first aspect of the present invention, the particles removed by the cleaning member and the cleaning liquid used for cleaning can be quickly discharged as the cleaning member rotates.

Further, in the present invention, the concentrically washing base cleaning surface may be provided with one or more guiding grooves communicating with the communication groove adjacent (claim 3).

  With this configuration, the particles removed by the cleaning member and the cleaning liquid used for cleaning can be actively guided and discharged to the communication groove and the discharge hole by the guide groove.

Moreover, in this invention, it is good also as a structure further equipped with the drainage pipe connected to said each discharge hole, and the suction means interposed by this drainage pipe (Claim 4 ).

  With this configuration, the particles removed by the cleaning member and the cleaning liquid used for cleaning can be efficiently discharged. In addition, since it can be positively discharged by the suction means, it is possible to adjust the rotational speed of the cleaning member and the supply amount of the cleaning liquid.

  According to this invention, since it is configured as described above, the following remarkable effects can be obtained.

  (1) According to the first aspect of the present invention, the particles removed by the cleaning member and the cleaning liquid used for cleaning can be discharged from the communication groove and the discharge hole to the cleaning back surface side. The generation of mist due to the cleaning liquid scattered on the substrate can be suppressed, and reattachment to the substrate can be prevented. Further, the number of rotations of the cleaning member is set high by discharging the particles removed by the cleaning member and the cleaning liquid used for cleaning to the cleaning back surface side without discharging from the outer peripheral side (periphery side) of the cleaning member. Therefore, the cleaning efficiency can be improved. In this case, the cleaning base is formed with a larger diameter than the cleaning liquid outlet of the base portion, and the cleaning liquid outlet and the buffer communication hole communicating with each communication groove are provided to discharge (supply) from the cleaning liquid outlet. Since the cleaning liquid to be discharged can be made to flow evenly and smoothly to each communication groove, a clean cleaning liquid can always be supplied (claim 2).

(2) According to the first aspect of the present invention, the particles removed by the cleaning member and the cleaning liquid used for cleaning can be discharged quickly as the cleaning member rotates. In addition, the cleaning efficiency can be further improved.

(3) According to the invention described in claim 3 , since the particles removed by the cleaning member and the cleaning liquid used for cleaning can be positively guided and discharged to the communication groove and the discharge hole by the guide groove, In addition to the above (1) and (2), the cleaning efficiency can be further improved.

(4) According to the invention described in claim 4 , the suction means is connected to the drain pipe communicating with each discharge hole, so that the particles removed by the cleaning member and the cleaning liquid used for cleaning can be efficiently discharged. Therefore, in addition to the above (1) to (3), generation of mist can be further suppressed, and reattachment to the substrate can be prevented. Further, by positively discharging by the suction means, the rotation speed of the cleaning member and the supply amount of the cleaning liquid can be adjusted, so that the cleaning process can be performed in an optimum state.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the best embodiment of the present invention will be described in detail with reference to the accompanying drawings. Here, when the substrate cleaning apparatus according to the present invention is installed near the exit of the semiconductor wafer resist coating / development processing system, the back surface of the wafer on which the resist film is formed is cleaned and then sent to the subsequent exposure apparatus. Will be described.

  FIG. 1 is a schematic plan view of a resist coating / developing system, FIG. 2 is a schematic perspective view of the resist coating / developing system, and FIG. 3 is a schematic longitudinal sectional view of the resist coating / developing system.

  The resist coating / development processing system is provided with a carrier block S1, and the transfer arm C takes out the wafer W from the sealed carrier 100 mounted on the mounting table 101 and transfers it to the processing block S2. The transfer arm C is configured to receive the processed wafer W from S <b> 2 and return it to the carrier 100.

  The substrate cleaning apparatus 1 (hereinafter referred to as the cleaning apparatus 1) according to the present invention transfers the wafer W from the processing block S2 to the exposure apparatus S4, that is, at the entrance of the interface block S3 as shown in FIG. The back surface of the wafer W to be processed is cleaned.

  As shown in FIG. 2, the processing block S <b> 2 is a first block (DEV layer) B <b> 1 for performing development processing in this example, and a processing for forming an antireflection film formed on the lower layer side of the resist film. The second block (BCT layer) B2, the third block (COT layer) B3 for applying the resist film, and the fourth block for forming the antireflection film formed on the upper layer side of the resist film (TCT layer) B4 is laminated in order from the bottom.

  The second block (BCT layer) B2 and the fourth block (TCT layer) B4 are each a coating unit that applies a chemical solution for forming an antireflection film by spin coating, and a process performed in this coating unit. A heating / cooling system processing unit group for performing the pre-processing and post-processing, and transfer arms A2 and A4 that are provided between the coating unit and the processing unit group and transfer the wafer W between them. , Is composed of. The third block (COT layer) B3 has the same configuration except that the processing solution is a resist solution.

  On the other hand, with respect to the first block (DEV layer) B1, as shown in FIG. 3, the developing units 110 are stacked in two stages in one DEV layer B1. In the DEV layer B1, a transfer arm A1 for transferring the wafer W to the two-stage development unit 110 is provided. That is, the transport arm A1 is made common to the two-stage development unit.

  Further, as shown in FIGS. 1 and 3, the processing block S2 is provided with a shelf unit U5, and the wafer W from the carrier block S1 is one transfer unit of the shelf unit U5, for example, a second block (BCT layer). ) It is sequentially transported to the corresponding delivery unit CPL2 of B2 by a first delivery arm D1 which can be raised and lowered provided in the vicinity of the shelf unit U5. Next, the wafer W is transferred from the transfer unit CPL2 to each unit (antireflection film unit and heating / cooling processing unit group) by the transfer arm A2 in the second block (BCT layer) B2, and is transferred to these units. Thus, an antireflection film is formed.

  Thereafter, the wafer W is transferred to the third block via the delivery unit BF2 of the shelf unit U5, the first delivery arm D1 that can be raised and lowered provided in the vicinity of the shelf unit U5, the delivery unit CPL3 of the shelf unit U5, and the transfer arm A3. (COT layer) It is carried into B3 and a resist film is formed. Further, the wafer W is transferred from the transfer arm A3 to the transfer unit BF3 of the shelf unit U5. The wafer W on which the resist film is formed may further have an antireflection film formed in the fourth block (TCT layer) B4. In this case, the wafer W is transferred to the transfer arm A4 via the transfer unit CPL4. After the antireflection film is formed, the wafer W is transferred to the transfer unit TRS4 by the transfer arm A4.

  On the other hand, in the upper part of the DEV layer B1, a shuttle arm E which is a dedicated transfer means for directly transferring the wafer W from the transfer unit CPL11 provided in the shelf unit U5 to the transfer unit CPL12 provided in the shelf unit U6. Is provided. The wafer W on which the resist film and further the antireflection film are formed is transferred from the transfer units BF3 and TRS4 to the transfer unit CPL11 via the transfer arm D1, and from there to the transfer unit CPL12 of the shelf unit U6 by the shuttle arm E. Directly conveyed. Here, as shown in FIG. 1, the transfer arm D2, which is a transfer means installed between the shelf unit U6 and the cleaning apparatus 1, is configured to be rotatable, advanced / retracted and raised / lowered, and specializes in wafers W before and after cleaning. For example, two arms are provided. The wafer W is taken out from the transfer unit TRS12 by an arm dedicated for cleaning before the transfer arm D2, and is carried into the cleaning apparatus 1 according to the present invention and subjected to back surface cleaning. After the cleaning, the wafer W is mounted on the transfer unit TRS13 by a dedicated arm after the transfer arm D2 is cleaned, and then taken into the interface block S3. Note that the delivery unit with CPL in FIG. 3 also serves as a cooling unit for temperature control, and the delivery unit with BF also serves as a buffer unit on which a plurality of wafers W can be placed. .

  Next, after being transported to the exposure apparatus S4 by the interface arm B and performing a predetermined exposure process here, it is placed on the delivery unit TRS6 of the shelf unit U6 and returned to the processing block S2. Next, the wafer W is developed in the first block (DEV layer) B1, and is transferred to the transfer unit TRS of the shelf unit U5 by the transfer arm A1. After that, the first transfer arm D1 is transported to the transfer unit in the access range of the transfer arm C in the shelf unit U5 and returned to the carrier via the transfer arm C. In FIG. 1, U <b> 1 to U <b> 4 are thermal system unit groups in which a heating unit and a cooling unit are stacked.

  Next, the cleaning apparatus 1 according to the present invention will be described in detail with reference to FIGS.

<First Embodiment>
4 is a perspective view (a) of the cleaning device 1 and an enlarged perspective view (b) of the I part of FIG. 5 (a), FIG. 5 is a plan view of the cleaning device 1, and FIG. is there.

  The cleaning apparatus 1 includes a suction pad 10 as a first substrate holding means for sucking and holding the wafer W received from the second delivery arm D2 in the resist coating / development processing system substantially horizontally, and the suction pad 10 A box-shaped undercup having an open top surface includes a spin chuck 20 that serves as a second substrate holding means that receives and holds the wafer W substantially horizontally, and a cleaning member 30 that cleans the back surface of the wafer W. 40 is attached.

  As shown in FIG. 4, two suction pads 10 are provided in the cleaning device 1, and each of the suction pads 10 is composed of, for example, an elongated block. The two suction pads 10 are arranged so as to support and hold the vicinity of the peripheral edge portion (first region) of the back surface of the wafer W substantially in parallel. The suction pad 10 is connected to a suction pipe (not shown) and has a function as a vacuum chuck that holds the wafer W while sucking it through the suction hole 11 shown in FIG. As shown in FIG. 4, each suction pad 10 is attached to a substantially central portion of an elongated rod-like pad support portion 12, and both end portions of these two pad support portions 12 are respectively connected to two girder portions 13. By being attached, the cross beam 14 which consists of the pad support part 12 and the girder part 13 is comprised.

  The two ends of the two spar 13 are two timings extending along these side walls on the outer side of the two opposing side walls of the undercup 40 (the side walls on the front side and the back side in FIG. 1). Each is fixed to a belt 15. Each timing belt 15 is wound around a set of two pulleys 16, and each pulley 16 is attached to two side plates 17 installed in parallel with the two side walls described above. One of the pulleys 16 is connected to a moving mechanism 19 serving as a moving means. The girder 13 is moved via the pulley 16 and the timing belt 15 so that the entire cross girder 14 is moved in the X direction shown in FIGS. It is configured so that it can be moved freely.

  Further, as shown in FIG. 4, each side plate 17 is supported at its bottom by a pair of elevating mechanisms 18 including an elevating part 18a and a cylinder part 18b elevating and lowering the elevating part 18a. It is fixed to the chassis floor. One of these elevating mechanisms 18 is provided with a drive mechanism (not shown) so that the elevating section 18a can be moved up and down in the cylinder section 18b so that the entire well 14 can be moved up and down in the Z direction in the figure. It is configured.

  Further, a donut-shaped upper cup 41 for straddling the cleaning liquid is straddled on the cross beam 14. An opening 42 having a larger diameter than the wafer W is provided on the upper surface of the upper cup 41, and the wafer W can be transferred between the transfer means and the suction pad 10 through the opening 42. It is like that. The upper cup 41 straddled on the cross beam 14 is configured to move in the X direction and the Z direction with the movement of the cross beam 14 as shown in FIG.

  The spin chuck 20 is a disc that supports the central portion (second region) of the back surface of the wafer W from below. The spin chuck 20 is installed in the middle of two suction pads 10 arranged substantially in parallel, and is a first region on the back surface of the wafer W supported by the respective substrate holding means (suction pad 10 and spin chuck 20). And the second region do not overlap. As shown in FIG. 6, the spin chuck 20 is connected to a drive mechanism such as a spin chuck motor 22 via a shaft portion 21, and the spin chuck 20 is configured to be rotatable and raised and lowered by the spin chuck motor 22. Similarly to the suction pad 10, the spin chuck 20 is also connected to a suction tube (not shown), and has a function as a vacuum chuck that holds the wafer W while sucking it through the suction hole 11 shown in FIG. .

  On the side of the spin chuck 20, support pins 24 connected to an elevating mechanism 23 are provided so as to be able to move up and down while supporting the back surface of the wafer W. The wafer W can be transferred from the suction pad 10 to the suction pad 10 and from the spin chuck 20 to the transfer means.

  Further, as shown in FIG. 4, an air knife 25 that is a surrounding member surrounding these devices is installed around the spin chuck 20 and the support pin 24. The air knife 25 has a gas injection port 26 formed along the circumferential direction at the upper end of a cylinder (enclosure member), and a cleaning liquid is blown out by blowing a gas such as compressed air from the injection port 26 toward the back surface of the wafer W. When the wafer W is delivered to the spin chuck 20 by blowing it to the outside of the cylinder, the surface of the spin chuck 20 and the back surface (second region) of the substrate supported by the spin chuck 20 are dried together. Serves as a drying means to make contact with. As shown in FIG. 17, the air knife 25 is composed of, for example, a double cylinder, and can supply a gas supplied from a supply unit (not shown) to the injection port 26 through a hollow part between the double cylinders. .

  Next, the cleaning member 30 for cleaning the back surface of the wafer W will be described with reference to FIGS. The cleaning member 30 is formed of a disk-shaped cleaning base 31 formed of, for example, a PVA (polyvinyl alcohol) sponge, and a plastic disk-shaped base 32 bonded to the lower surface of the cleaning base 31, for example. A cleaning liquid discharge port 33 (hereinafter referred to as a discharge port 33) connected to the cleaning liquid supply source 50 is provided at the center of the base portion 32 and the cleaning base portion 31.

  In this case, the discharge port of the cleaning base 31 is formed with a larger diameter than the discharge port 33 of the base portion 32. In addition, a plurality of communication grooves 35 (the four cases are shown in the drawing) are provided on the outer peripheral portion of the cleaning base 31 and the base end communicates with the communication hole 34 and the tip extends to the front of the outer peripheral edge of the cleaning member 30. It has been.

  A plurality of (four) elongated holes 36 that communicate with the respective communication grooves 35 are provided in the base portion 32 where the communication grooves 35 are located. An attachment portion 37 that communicates with the discharge port 33 and is connected to the cleaning liquid supply source 50 via the cleaning liquid supply pipe 51 is provided on the lower surface of the central portion of the base portion 32. A male screw 37a is engraved on the outer periphery of the attachment portion 37, and a support shaft 38 having a communication path 38a is connected to the attachment portion 37 via a coupler 37b. Further, the lower end of the support shaft 38 is connected to a servo motor 39 which is a rotation mechanism, and the cleaning member 30 is configured to be rotatable around the vertical axis by driving the servo motor 39.

  The cleaning member 30 is attached to the tip of a support member 60 that supports the cleaning member 30, and the support member 60 has a shape bent in a crank shape so as not to interfere with the wafer W and the beam portion 13. The base end of the support member 60 is fixed to a timing belt 61 stretched along the side wall on the back side when the cleaning member 30 is viewed from the direction in which the spin chuck 20 is installed in FIG. The timing belt 61 is wound around two pulleys 62, and these pulleys 62 are attached to the outer side wall on the back side. One of the pulleys 62 is connected to a moving mechanism 63, and the cleaning member 30 can be freely moved in the Y direction shown in FIGS. 4 and 5 via the timing belt 61 and the support member 60.

  The cleaning liquid supply pipe 51 is provided with an on-off valve 52 and a flow rate adjusting valve 53 from the cleaning liquid supply source 50 side toward the cleaning member 30 side. The flow rate adjusting valve 53 and the servo motor 39 are electrically connected to a controller which is a control means (not shown), and the flow rate of the cleaning liquid and the rotation speed of the cleaning member 30 are controlled based on a control signal from the controller. ing.

  The cleaning member 30 configured as described above rotates around the vertical axis by the drive of the servo motor 39 with the upper cleaning surface close to the lower surface of the wafer W, and at the same time, the cleaning liquid supplied from the cleaning liquid supply source 50. Is discharged (supplied) from the discharge port 33, and the particles on the lower surface of the wafer W can be removed by sliding in a state where a liquid film of the cleaning liquid is formed between the wafer W rotating horizontally by driving the spin chuck 20. At this time, as shown in FIG. 16, the cleaning liquid used for cleaning communicates among the liquid film F formed between the lower surface (surface to be cleaned) of the wafer W and the upper surface (cleaning surface) of the cleaning member 30. It is discharged downward from a discharge hole 36 that opens downward through the groove 35. Therefore, it is possible to prevent the cleaning liquid used for cleaning from hitting the upper cup 41 and being scattered to generate mist.

  As shown in FIG. 10, at least the communication groove 35 of the communication groove 35 and the discharge hole 36 is provided with an inclined surface 35a from the cleaning surface side toward the cleaning back surface side along the rotation direction of the cleaning member 30. Also good. Specifically, as shown in FIG. 10A, the communication groove 35 and the discharge hole 36 are provided with an inclined surface 35a from the cleaning surface side to the cleaning back surface side along the rotation direction R of the cleaning member 30, Alternatively, as shown in FIG. 10 (b), the communication groove 35 is provided with an inclined surface 35a from the cleaning surface side to the cleaning back surface side along the rotation direction R of the cleaning member 30, and the discharge hole 36 is connected to the communication hole in an inclined shape. You may form in the perpendicular | vertical shape connected to the lower end opening part 35b of the groove | channel 35. FIG.

  As described above, at least the communication groove 35 of the communication groove 35 and the discharge hole 36 is provided with the inclined surface 35a from the cleaning surface side toward the cleaning back surface side along the rotation direction of the cleaning member 30, thereby cleaning member 30. The particles removed by cleaning and the cleaning liquid used for cleaning can be quickly discharged as the cleaning member 30 rotates.

  Further, as shown in FIGS. 11 and 12, a guide groove 35 c communicating with the adjacent communication groove 35 may be provided on a concentric circle on the cleaning surface of the cleaning base 31 of the cleaning member 30. Although two guide grooves 35c are provided in the drawing, one or three or more guide grooves may be provided.

  With this configuration, the particles removed by the cleaning member 30 and the cleaning liquid used for cleaning can be positively guided and discharged to the communication groove 35 and the discharge hole 36 by the guide groove 35c.

  In addition, as shown in FIG. 6, a drain pipe 43 for discharging the cleaning liquid accumulated in the undercup 40 and two exhausts for exhausting the airflow in the cleaning device 1 are provided at the bottom of the undercup 40. A tube 44 is provided. The exhaust pipe 44 is extended upward from the bottom surface of the under cup 40 to prevent the cleaning liquid accumulated at the bottom of the under cup 40 from flowing into the exhaust pipe 44, and the cleaning liquid dripping down from above is supplied to the exhaust pipe 44. In order not to enter directly, it is covered with an inner cup 45 forming a ring-shaped cover attached around the air knife 25.

  A blow nozzle 46 is disposed above the opening 42 of the upper cup 41 to assist in drying the remaining cleaning liquid by spraying compressed air or the like from above on the vicinity of the outer periphery of the wafer W after the cleaning of the wafer W. Has been. The blow nozzle 46 includes an elevating mechanism (not shown), and retracts upward so as not to interfere with the wafer W being transferred and the transfer means when the wafer W is loaded / unloaded. A cleaning liquid nozzle 47 for supplying the cleaning liquid from the cleaning member 30 and supplying the cleaning liquid to the back surface of the wafer W is provided on the inner side of the upper cup 41.

  A lamp box 49 containing a UV lamp 48 is attached to the side wall of the under cup 40 where the timing belts 15 and 61 are not stretched. The wafer W to be processed is transferred into and out of the cleaning apparatus 1 from the left X direction, and passes above the UV lamp 48 at that time. The UV lamp 48 serves to irradiate the back surface of the wafer W, which has been cleaned and carried out, with ultraviolet light, and to shrink particles remaining on the back surface of the wafer W.

  Further, as shown in FIG. 5, each of the moving mechanisms 19, 63, the UV lamp 48, the pressure adjusting unit (not shown) provided in the exhaust pipe 44, and the like are controllers that are control means for controlling the entire operation of the coating and developing apparatus. 70 is controlled. The controller 70 includes, for example, a computer having a program storage unit (not shown). The wafer W received from the external transfer device is transferred between the suction pad 10 and the spin chuck 20 or cleaned by the brush 5 in the program storage unit. A computer program having a group of steps (instructions) for the operation or the like is stored. Then, when the computer program is read by the controller 70, the controller 70 controls the operation of the cleaning device 1. The computer program is stored in the program storage unit while being stored in a storage unit such as a hard disk, a compact disk, a magnetic optical disk, or a memory card.

  Based on the configuration described above, the operation of cleaning the back surface of the wafer W will be described with reference to FIGS. 14 and 15 are schematic longitudinal sectional views for explaining each operation of the cleaning apparatus 1 relating to the back surface cleaning of the wafer W. FIG. FIG. 16 is a schematic cross-sectional view showing a cleaning state of the cleaning member 30, and FIG. 17 is a schematic cross-sectional view showing a state of the lower surface of the wafer W during cleaning. FIG. 18 is a schematic plan view schematically showing a region to be cleaned of the wafer W in each state held by the suction pad 10 or the spin chuck 20. In these drawings, the description of the UV lamp 48, the blow nozzle 46, and the like is omitted as appropriate for convenience of illustration.

  As shown in FIG. 14A, for example, a horseshoe-shaped transfer means (second delivery arm D2) carries the processing target wafer W into the cleaning apparatus 1 and stops above the opening 42 of the upper cup 41, The support pin 24 rises from below the spin chuck 20 and stands by below the conveying means. The transfer means descends from above the support pins 24, transfers the wafer W to the support pins 24, and exits from the cleaning apparatus 1. At this time, the suction pad 10 stands by at a position where the surface holding the wafer W is higher than the upper surface of the cleaning member 30, and the spin chuck 20 is retracted to a position lower than the upper surface of the cleaning member 30. Due to such a positional relationship, when the support pins 24 are lowered, the wafer W is first delivered to the suction pad 10 (FIG. 14B).

  Thereafter, the suction pad 10 sucks and holds the wafer W and moves to the right while holding the wafer W. Then, after the wafer W is transferred to a predetermined position (for example, a position where the left end of the air knife 25 substantially coincides with the left end of the wafer W), the suction pad 10 is lowered and the back surface of the wafer W is removed from the cleaning member 30. Press against the top surface (FIG. 14C).

  Next, after the air knife 25 is operated to prevent the cleaning liquid from flowing around and adhering to the surface of the spin chuck 20, the cleaning member 30 adjacent to the lower surface of the wafer W is rotated and from the discharge port 33 of the cleaning member 30. The cleaning liquid is supplied to start cleaning the back surface of the wafer W. The back surface cleaning proceeds by a combination of the movement of the wafer W by the suction pad 10 and the movement of the cleaning member 30. Specifically, for example, as shown in FIG. 18A, the cleaning member 30 reciprocates in the Y direction in the drawing, and the suction pad is shorter than the diameter of the cleaning member 30 when the moving direction of the cleaning member 30 is switched. 10 is moved in the left X direction. As a result, the cleaning member 30 moves along the back surface of the wafer W while following a trajectory as indicated by an arrow, and the region T1 filled with the upper left diagonal line in FIG.

  During the cleaning period, the entire back surface of the wafer W is covered with the cleaning liquid film F as shown in FIGS. 16 and 17, and the particles removed by the cleaning member 30 are used for cleaning. It flows to the under cup 40 below through the communication groove 35 and the discharge hole 36 of the cleaning member 30 together with the cleaning liquid. Therefore, as shown in FIG. 16, it is possible to prevent the cleaning liquid containing particles removed by the cleaning member 30 from hitting the inner wall of the upper cup 41 and scattering to generate mist. The particles removed by the other cleaning members 30 are washed out to the under cup 40 together with the cleaning liquid that flows down from the back surface of the wafer W. Further, gas is ejected from the ejection port 26 of the air knife 25 toward the back surface of the wafer W, and the cleaning liquid is blown off toward the outside of the air knife 25, so that the back surface of the wafer W facing the air knife 25 is kept dry. (See FIG. 17). With such a configuration, it is possible to prevent the cleaning liquid covering the back surface of the wafer W from entering the inside of the air knife 25. As a result, the surface of the spin chuck 20 is always maintained in a dry state, and it becomes possible to prevent contamination by the processed cleaning liquid and formation of a watermark.

  When the cleaning of the region T1 is completed, the suction pad 10 is moved to position the center portion of the wafer W above the spin chuck 20 (FIG. 15A), and then the wafer from the suction pad 10 to the spin chuck 20 is moved. Deliver W. For example, the wafer W is transferred by stopping the movement and rotation of the cleaning member 30 while supplying the cleaning liquid while the air knife 25 is operated, and releasing the suction of the wafer W by the suction pad 10 while retracting the spin chuck 20. Is raised to support the back surface of the wafer W, and then the suction pad 10 is retracted downward.

  The spin chuck 20 that has transferred the wafer W sucks and holds the wafer W at substantially the same height as the suction pad 10, so that the cleaning member 30 is close to the lower surface (surface to be cleaned) of the wafer W. Then, the cleaning member 30 is rotated again and the cleaning liquid is supplied to resume the back surface cleaning (FIG. 15B). At this time, the back surface cleaning proceeds by a combination of rotation of the spin chuck 20 and movement of the cleaning member 30. Specifically, for example, as shown in FIG. 18B, first, the cleaning member 30 is moved to a position where the outermost periphery of the wafer W can be cleaned, and then the wafer W is slowly rotated to rotate the wafer W once. Then, the same operation is repeated after the cleaning member 30 is moved to a position where the inner peripheral surface can be cleaned by the diameter of the cleaning member 30 rather than the annular region cleaned by the previous operation. By such an operation, the back surface of the wafer W is moved while drawing a concentric circular orbit, and the region T2 filled with the upper right oblique line in the figure can be washed evenly.

  Here, the region including the region T1 and the region T2 includes the entire back surface of the wafer W as shown in FIG. 18B, and the size and movement range of each device so as not to cause a dead space that is not cleaned. Has been adjusted. During the period in which the wafer W is held by the spin chuck 20 for cleaning, not only the cleaning liquid is supplied from the cleaning member 30 but also the cleaning installed on the left side of the air knife 25 in FIG. A cleaning liquid is also supplied from the nozzle 47. The reason why the cleaning liquid is supplied also from the cleaning nozzle 47 as described above is that when a wet area and a dry area are mixed on the surface of the wafer W, a watermark is generated when the cleaning liquid is dried. Therefore, the cleaning liquid is spread evenly to suppress the generation of watermarks.

  When the cleaning of the entire back surface of the wafer W is thus completed, the rotation and movement of the cleaning member 30, the supply of the cleaning liquid, and the rotation of the spin chuck 20 are stopped, and the cleaning liquid is shaken and dried. The shake-off drying is performed by rotating the spin chuck 20 at a high speed to shake off the cleaning liquid adhering to the back surface of the wafer W. As described above, the generation of the watermark is suppressed by shaking the wafer W that has been uniformly wetted and drying it. At this time, the blow nozzle 46 that has been retreated upward is lowered, and at the same time, the support member 60 is moved so that the blow nozzle 46 beside the cleaning member 30 is positioned at the peripheral edge of the wafer W. Blow-off drying is promoted by blowing gas from the lower surface. The second region held by the spin chuck 20 cannot be shaken and dried, but since it is in contact with the spin chuck 20 while being dried by the air knife 25, a watermark is generated. There is almost no.

  When the cleaning and drying of the entire back surface of the wafer W is completed by the operation described above, the wafer W is transferred to the transfer means by the operation opposite to that at the time of loading and unloaded. At this time, even if the UV lamp 48 shown in FIGS. 4 to 6 is turned on and ultraviolet rays are irradiated from the lower side of the transfer means to the back surface of the wafer W in a horseshoe shape, For example, since organic substances are decomposed by irradiation with ultraviolet rays, it is possible to reduce the influence of defocusing and the like by shrinking such type of particles.

  In parallel with the unloading operation of the wafer W, the suction pad 10 and the spin chuck 20 move to the position shown in FIG. 14A and wait for the next wafer W to be loaded. Then, the operations described with reference to FIGS. 14 to 18 are repeated to sequentially wash the plurality of wafers W.

Second Embodiment
FIG. 19 is a schematic sectional view showing a second embodiment of the cleaning apparatus according to the present invention.

  In the second embodiment, the particles removed by the cleaning member 30 and the cleaning liquid used for cleaning are positively discharged. That is, as shown in FIG. 19, a drainage pipe 81 is connected (connected) to each discharge hole 36 provided in the cleaning member 30, and a suction pump 80 that is a suction means is connected to the drainage pipe 81. This is a case where the particles removed by the cleaning member 30 and the cleaning liquid used for cleaning are positively discharged. In this case, the rotation mechanism of the suction pump 80 and the cleaning member 30, that is, the servo motor 39 and the flow rate adjusting valve 53 provided in the cleaning liquid supply pipe 51 are electrically connected to the controller 70 as control means. It is comprised so that it may be controlled based on the control signal from. In the second embodiment, the other parts are the same as those in the first embodiment.

  According to the cleaning apparatus 1 of the second embodiment configured as described above, the particles removed by the cleaning and the cleaning liquid used for the cleaning can be efficiently discharged. Further, since it can be positively discharged by the suction action of the suction pump 80, the rotation speed of the cleaning member 30 and the supply amount of the cleaning liquid can be adjusted, and the cleaning process can be performed in an optimum state. Become.

  In addition, by using the cleaning apparatus 1 of the second embodiment, it is possible to apply the cleaning process for the upper surface of the wafer W in addition to the cleaning for the lower surface of the wafer W.

<Other embodiments>
In the resist coating / development processing system shown in FIGS. 1 to 3, an example in which the cleaning device 1 according to the embodiment is provided at the inlet of the interface block S3 is shown. It is not limited to examples. For example, the cleaning apparatus 1 may be installed in the interface block S3, or the wafer W before the resist film is formed on the entrance of the processing block S2, for example, the shelf unit U5, is configured to clean the back surface. Alternatively, it may be provided in the carrier block S1.

  Furthermore, the apparatus to which the cleaning apparatus 1 according to this embodiment can be applied is not limited to the resist coating / development processing system. For example, the cleaning apparatus 1 can be applied to a heat treatment apparatus that performs an annealing process after ion implantation. If the annealing process is performed with the particles attached to the back surface of the wafer W, the particles may enter from the back surface of the wafer during this process, and a current path may be formed between the particles and the transistors on the surface. For this reason, the yield of products can be improved by cleaning the back surface of the wafer W before this process.

  In the above-described embodiment, the case where the cleaning apparatus according to the present invention is applied to a resist coating / development processing system for a semiconductor wafer has been described. It can also be applied to substrates.

  Next, an evaluation experiment performed to examine the cleaning efficiency of the cleaning member 30 and the conventional cleaning member in the cleaning apparatus according to the present invention will be described.

<Evaluation conditions>
Sample: Comparative example {cleaning member having a cleaning liquid discharge port at the center}
Example {Cleaning member 30 according to the first embodiment}
・ Pushing force: 0.8N
・ Rotation speed of cleaning member: 500 rpm
Cleaning member rinse: 0.0 L / min.
-Bath DIW flow rate: 0.2 L / min.
・ Sample substrate: wafer with PSL (Polystyrene Latex) attached
(Hydrophilic: 0.309μm, 15000 adheres)
Measuring instrument: SP1 (# 1 2F) = SurfscanSp1TB1 (BZ-0200,
BZ-0104) {KLA-Tencor Ltd. Product name}
・ Inspection conditions: Inspection particle size 0.10 μm, 0.16 μm, 0.20 μm, 1.0 μm
-Inspection area: φ65-296mm
-Experimental machine: Brush cleaning module.

<Evaluation method>
First, the cleaning members of the comparative example and the example are sufficiently immersed in water with a cleaning bath. Next, the position where the cleaning member pressure becomes zero is set as the cleaning member pushing amount zero, and after adjusting the pushing amount to 2.5 mm, the initial of the wafer (sample substrate) is measured by the measuring instrument (SP1). Next, parameters are set, the sample is cleaned by a bath cleaning mechanism for a predetermined time, an actual sample is processed, and the number of particles after processing is measured by the measuring instrument (SP1).

As a result of the evaluation experiment, the results shown in Table 1 were obtained in the comparative example, and the results shown in Table 2 were obtained in the example.

  As a result of the above evaluation experiment, it was found that according to the embodiment using the cleaning member in the cleaning apparatus according to the present invention, the particle removal rate is significantly higher than that of the conventional cleaning member (comparative example).

1 is a schematic plan view showing an example of a resist coating / development processing system to which a substrate cleaning apparatus according to the present invention is applied. It is a schematic perspective view of the said resist application | coating / development processing system. It is a schematic longitudinal cross-sectional view of the said resist application | coating / development processing system. It is the perspective view (a) which shows 1st Embodiment of the board | substrate cleaning apparatus based on this invention, and the I section expansion perspective view (b) of (a). It is a top view of the said substrate cleaning apparatus. It is sectional drawing of the said board | substrate cleaning apparatus. It is a cross-sectional perspective view which shows the cleaning member in this invention. It is a top view of the above-mentioned cleaning member. It is sectional drawing which follows the II-II line of FIG. It is sectional drawing which shows another modification of the communicating groove | channel and discharge hole in this invention, Comprising: It is sectional drawing which follows the III-III line | wire of FIG. It is a top view which shows another form of the washing | cleaning member in this invention. It is sectional drawing which follows the IV-IV line of FIG. It is a perspective view which shows the air knife in the board | substrate cleaning apparatus of 1st Embodiment. It is a schematic sectional drawing of the 1st process for demonstrating operation | movement of the board | substrate cleaning apparatus of 1st Embodiment. It is a schematic sectional drawing of the 2nd process for demonstrating operation | movement of the board | substrate cleaning apparatus of 1st Embodiment. It is a schematic sectional drawing which shows the cleaning state of the cleaning member in this invention. It is a schematic sectional drawing which shows the state of the wafer lower surface at the time of washing | cleaning. It is a schematic plan view which shows the area | region cleaned in each operation | movement of the board | substrate cleaning apparatus of 1st Embodiment. It is sectional drawing which shows 2nd Embodiment of the board | substrate cleaning apparatus which concerns on this invention.

Explanation of symbols

W Semiconductor wafer (substrate to be processed)
F Liquid film R Rotation direction 10 Suction pad (holding means)
20 Spin chuck (holding means)
22 Spin chuck motor 30 Cleaning member 31 Cleaning base 32 Base 33 Discharge port (cleaning liquid discharge port)
34 Communication hole (cleaning liquid discharge port)
35 Communication groove 35a Inclined surface 35c Guide groove 36 Discharge hole 50 Cleaning liquid supply source 51 Cleaning liquid supply pipe 53 Flow rate adjusting valve 70 Controller (control means)
80 Suction pump (suction means)
81 Drainage pipe

Claims (4)

A holding means for holding the substrate to be processed horizontally and rotating about the vertical axis, a cleaning member that can rotate about the vertical axis, a rotating mechanism for rotating the cleaning member, and the cleaning member that covers the substrate to be processed. In a substrate cleaning apparatus comprising a moving mechanism that moves along a cleaning surface,
The cleaning member is formed by joining a sponge-like cleaning base to the base portion,
A cleaning liquid discharge port connected to a cleaning liquid supply source is provided at the center of the base part and the cleaning base part.
In the cleaning base, a base end communicates with the cleaning liquid discharge port, and a plurality of communication grooves extending to the front side of the outer peripheral edge of the cleaning member are provided,
In the portion of the base portion where the communication groove is located, a discharge hole that communicates with the communication groove is provided ,
At least the communication groove of the communication groove and the discharge hole has an inclined surface from the cleaning surface side toward the cleaning back surface side along the rotation direction of the cleaning member.
A substrate cleaning apparatus. The substrate cleaning apparatus according to claim 1,
A substrate cleaning apparatus, further comprising a buffer communication hole formed at a central portion of the cleaning base and having a diameter larger than that of the cleaning liquid discharge port of the base portion and communicating with the cleaning liquid discharge port and each communication groove. The substrate cleaning apparatus according to claim 1 or 2 ,
A substrate cleaning apparatus, wherein one or a plurality of guide grooves communicating with adjacent communication grooves are provided on concentric circles on the cleaning surface of the cleaning base. The substrate cleaning apparatus according to any one of claims 1 to 3 ,
A substrate cleaning apparatus, further comprising: a drain pipe communicating with each of the discharge holes; and a suction means interposed in the drain pipe.

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